Gusset type envelopes



July 19, 1960 w. o. NORMANDIN GUSSET TYPE ENVELOPES Filed Nov. 25, 1956Inmwlin W/L m M 0. NW: MAND/IV United States. Patent GUSSET TYPEENVELOPES Filed Nov. 23, 1956, Ser. No. 624,062

1 Claim. (Cl. 229 -68) The present invention relates to the manufactureof gusset type envelopes and more particularly to an unproved form ofgusset type envelope particularly suited for manufacture by automaticenvelope-making machines.

Gusset type or envelopes having expansible sides are generally wellknown and are presently available in many varieties and sizes. However,due to their construction, they are not suited for automatic machinefolding and assembly and therefore are mainly made by hand which, ofcourse, makes the production cost and labour involved a considerableitem.

The present invention recognizes this problem and aims to provide agusset type envelope adapted to be made from a one-piece blank that isparticularly suited for machine folding and assembly, for example by theimproved envelope-making machine illustrated and described in theapplicants US. Patent 2,899,874, issued April 28, 1958.

Accordingly, the invention is a one-piece envelope blank which is shapedand scored so that when folded and adhesively secured forms a gussettype envelope having coextensive front and back panels interconnected bycentrally folded expansible side and bottom panels of equal width and atop closure flap of substantially equal width to and extending from saidfront panel. The closure flap is of considerably greater length than theexpanded width of the side and bottom panels so that it will span theexpandedwidth of the envelope and overlap the back panel for securingpurposes.

More specifically, the blank from which this envelope is made is shapedfrom a flat piece of flexible material, usually paper or lightcardboard, to provide a main central portion of substantiallyrectangular outline which, when the envelope is folded, constitutes thefront panel; side portions extending from each side of the centralportion which constitute the expansible side panels and the back panelof the envelope when secured in overlapped register with the frontpanel; a top portion, of equal width to and extending from one end ofthe central portion to constitute the closure flap; and a bottom portionof graduated width which extends from the combined side and centralportions and when folded forms the expansible bottom portion of theenvelope. The Width of the blank bottom portion varies from the maximumwidth at the point of juncture with the side and central portions to aminimum width at the terminal edge which is equal to the width of theblank central portion and at an intermediate point has a width greaterthan the blank central portion but less than the combined side andcentral portions.

Having thus generally described the nature of the invention, particularreference will be made to the accompanying drawing, illustrating theblank and envelope of the invention, and in which:

Figure l is a view in perspective elevation of a gusset type envelopehaving expansible side and bottom portions as made from the blank of theinvention;

Figure 2 is a cross-sectional view of the envelope shown in Figure 1along the line 2--2 and partially opened to illustrate the location ofthe various folds in more detail;

Figure 3 is a further cross-sectional view corresponding to Figure 2with the envelope in fiat condition;

Figure 4 is a partial cross-sectional view of the envelope constructionof Figure 1 along the line 4-4 to illustrate the folds of the expansiblebottom portion, the broken outline showing the bottom portion partiallyexpanded;

Figure 5 is an enlarged front view of the bottom portion of the envelopeshown in Figure 1 with the outer flap partially opened to show thearrangement of the side portion folds prior to the final folding in;

Figure 6 is a cross-sectional View of Figure 5 along the line 6-6 toillustrate the disposition of the side portion folds and bottom portionflap;

Figure 7 is an enlarged fragmentary detail view'in perspective elevationof one corner of the envelope construction shown in Figure 1 as it wouldappear in full open condition;

Figure 8 is a view in plan of the one-piece blank from which theenvelope construction of Figure 1 is made with the various fold linesindicated in broken lines.

With particular reference to Figures 1 and 8, the preferred form ofenvelope with which the present invention is concerned is shown in blankform in Figure 8 and in made-up form in Figure l.

The one-piece blank, made of suitable flexible sheet material, forexample paper or the like, is shaped so as to have a main centralportion 10 which will constitute the front panel of the envelope. Sideportions 12 extend from each side of the main blank portion 10 and thesewhen scored and folded will constitute the expansible side panels andthe back panel of the envelope. A top portion 14 extends from one end ofthe main portion 10 and this forms the envelope top closure flap. Abottom portion 16 extends from the combined side 12 and central portions10 and when scored and folded forms the expansible bottom portion of theenvelope.

The necessary scoring lines for the various folds are indicated indotted lines and for the purpose of the present description certain ofthese can be considered lines of'demarcation between the various blankportions. The triple score lines indicated at A on each side of theblank central portion show the fold lines for the double gusset fold ofthe side panels of the envelope indicated at 20. These fold lines Aextend the full length of the blank at each side of the central poltion10 to permit the later folding of the expansible bottom panel of theenvelope as will be described later. The double score lines B, B',indicate the line of demarcation and the fold lines for the bottomportion 16. The fold line B extends completely across the combined blankside portions 12 and the central portion 910 and when the envelope ismade up this fold line defines the line of demarcation between the frontpanel 22, the back panel 24, the side panels 20, and the extensiblebottom panel 26 made up from the blank bottom portion 16. The distancebetween the fold lines B and B is half the full extended width of theexpansible side panels 20 so that when the envelope is in full opencondition, as shown in Figure 7, the bottom panel 26 is equal to theopen width of the side panels. The bottom blank portion 16 is shapedfrom the maximum width at the fold line B to a reduced width at the foldline B"and finally to a width corresponding to the width of the blankcentral portion 10 at the lower terminal edge.

The fold lines C, C' indicate the scores or folds made in the blank topportion 14 forming the envelope closure flap 28. The distance betweenthe fold lines C, C' is substantially equal to the expanded width of theenvelope side panels. 20 so that the envelope top closure flap 28 willfold flatly over into sealed position when the enevelope is in use.

The blank is made up into the gusset type envelope by first scoring thefold lines C, C along the top portion 14, the triple fold lines A alongeach side of the blank central portion and the fold line B across thecombined side and central portions of the blank. The side portions 12 ofthe blank are then folded inwardly, outwardly and inwardly along thefold lines A producing the double folded envelope side panels andbringing the remaining free side portions 12 of the blank intooverlapping register on the front portion 10 to form the back panel 24of the envelope. Adhesive is previously applied along the overlappingmarginal edge or edges of the blank side portions 12 so that when theyare pressed flatly in overlapped register they are adhesively securedtogether. Adhesive is also applied to the lower marginal edge of theblank bottom portion 16, the score line B' is made and the terminal flapor minimum width portion of the blank bottom portion 16 is folded overthe envelope back panel 24 and adhesively secured thereto, see Figure 4.

As the score lines A extended the full length of the blank the sidesections of the blank bottom portion were also double folded, seeFigures 5 and 6, and when the fold along the line B is made these arefolded upwardly against the lower marginal edges of the back panel 24and the outer fold adhesively secured thereto. The envelope is now inthe finished fiat folded condition shown in Figure 1.

In use, when the envelope is expanded, the side panels 20 unfold, seeFigure 2, and the blank bottom portion 16 becomes the envelope bottompanel 26. The double folded side portions of the blank bottom portion 16between the fold lines B, B', form triangular expansion gussetsindicated at 25 allowing the envelope bottom panel 26 to expand flatlyacross the bottom of the envelope to correspond with the expanded sidepanels 20.

As previously mentioned, the envelope blank of the invention isparticularly suited for use in automatic envelope-making machinesmodified for this purpose. Prior art envelope blanks from which knowngusset type envelopes are made are not generally suitable for machineproduction since they are designed for manual folding and assembly.

I claim:

A preformed flat folded envelope of the fully expansible type made froma one-piece fiat blank adapted to be scored, folded, gummed andassembled in continuous in-line sequence on an automatic envelopemachine, said envelope comprising coextensive rectangular front and backpanels, side panels interconnecting respective opposite side edges ofthe front and back panels by side folds and said side panels each havingan intermediate fold parallel with and in reverse to the side folds todivide the Side panels into inwardly folded side sections lyingsubstantially flatly between said front and back panels when theenvelope is in flat condition, a bottom panel having a part joining withthe bottom edge of the front panel on a transverse line of fold andhaving a width corresponding with the width of the side panels, saidpart of the bottom panel having an intermediate fold extending parallelwith the transverse line of fold to provide bottom sections overlyingeach other and projecting outwardly from bottom portions of the frontand back panels when the envelope is in said fiat condition, said bottompanel also including parts comprising continuations of the sections ofthe side panels and parts depending from the back panel and engagedbetween the sections of said first named part of the bottom panel whenthe envelope is in said fiat condition and having lines of fold formingcontinuations of the said transverse line of fold and having foldsforming continuations of the intermediate fold of the first named partof the bottom panel, said extensions of the side sections of the sidepanels being of different lengths to provide sealing portions forcontact with parts of the bottom panel that depend from the back panel,and an adhesive connecting the sealing portions of the extensions of theside sections and the overlying section of the first named panel to thepart depending from the back panel to complete the bottom panel wherebywhen the envelope is fully expended a fiat bottom is provided by thehinging of the bottom and side panels on said folds while the front,back and side panels break along said transverse lines of fold and theportions of the extensions of the side sections which are locatedbetween the transverse score and the transverse fold are breakinginwardly to provide triangular gussets to bring the bottom panel in aright-angular plane with respect to planes of the front, back and sidepanels, a top panel having a part joining with the top edge of the frontpanel on a transverse line of fold and being of equal width to saidfront panel, said top panel part having an intermediate fold extendingparallel with said transverse line of fold spaced from said first fold adistance equal to the width of said side panels, and a flap portionextending beyond said intermediate fold and adapted to overlie the uppermarginal edge of said back panel.

References Cited in the file of this patent UNITED STATES PATENTS904,168 Widmer Nov. 17, 1908 2,000,796 Swift et a1 May 7, 1935 2,062,618Sterling Dec. 1, 1936 2,149,872 Schmidt Mar. 7, 1939 2,274,934 PiazzeMar. 3, 1942 2,329,444 Snyder Sept. 14, 1943 2,631,772 Hiersteiner Mar.17, 1953 2,688,914 Eckler Sept. 14, 1954 2,837,267 Potdevin et a1. June3, 1958

